In U.S. Pat. No. 4,918,249, issued Apr. 17, 1990, from application Ser. No. 338,916 filed Apr. 17, 1989, a process is disclosed and claimed wherein a feedstock comprising hydrocarbon or an oxygenated hydrocarbon having 1 to 10 carbon atoms is contacted at a temperature of about 350.degree. to 550.degree. C. with air or oxygen and in the presence of a catalytically effective amount of a catalyst containing crystalline silicometallate having iron incorporated in the structural framework.